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Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In Vitro Prion Protein Conversion Assay
Published on: March 10, 2015
Prion variants, species barriers, generation and propagation
Reed B Wickner1, Herman K Edskes, Frank Shewmaker
1Laboratory of Biochemistry and Genetics, National Institute of Diabetes Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA. wickner@helix.nih.gov
Journal of Biology
|June 13, 2009
Summary
Prion variants can cross species barriers, but high barriers select for new mutants. Protein sequence changes can disrupt structural templating, leading to altered prion variants.
Area of Science:
- Biochemistry
- Molecular Biology
- Structural Biology
Background:
- Prions are misfolded proteins that propagate by template-assisted conformational change.
- Prion propagation across species barriers is a complex process influenced by protein sequence homology.
- High species barriers can lead to the selection of novel prion strains or mutants.
Purpose of the Study:
- To investigate the mechanisms underlying prion variant selection when species barriers are high.
- To understand how protein sequence alterations affect prion structural templating and propagation.
Main Methods:
- Computational modeling of prion filament formation and propagation.
- Analysis of prion protein sequences and structural dynamics.
- In silico simulation of inter-species prion transmission.
Main Results:
- Protein sequence alterations were shown to interfere with accurate structural templating at prion filament ends.
- This disruption in templating facilitates the selection and propagation of new prion variants (mutants).
- The study provides a molecular explanation for prion adaptation under high species barriers.
Conclusions:
- Prion variant selection is driven by the interplay between species barriers and protein sequence.
- Altered protein sequences can lead to aberrant structural templating, resulting in the emergence of new prion strains.
- These findings enhance our understanding of prion evolution and cross-species transmission dynamics.
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